Elastic cap



FIG. 1 is a perspective view of an elastic cap showing my new design;

FIG. 2 is a top plan view thereof; and,

FIG. 3 is a side elevation view thereof.

The broken line showing of the human head in FIG. 1 is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for an elastic cap, as shown and described. 